Among wireless communication technologies, a multiple input multiple output (MIMO) transmission method, which is a multi-antenna technology, has been prominent. The MIMO applied to wireless communication provides a method capable of transceiving data (that may be referred to as a packet or a frame according to a technical field) using multiple antennas between a transmitter and a receiver.
Indices of determining performance of a wireless communication system may be a data throughput and a link range. The MIMO transmission method may improve a data throughput and a link range of wireless communication without an increase in a bandwidth of a usable frequency and a transmission power for data transmission. This MIMO transmission has been supported in IEEE 802.11n, 3GPP long term evolution (LTE), WiMAX, HSPA+, or the like. The tendency to apply the MIMO transmission to a digital video broadcasting (DVB) system has currently appeared.
The MIMO transmission may cause deterioration in performance in a channel environment in which correlation is generated in transmitting and receiving antennas. The existing MIMO transmission has been applied to a mobile communication system. In the case of the mobile communication system, since channel values between the transmitting and receiving antennas are designed on the assumption that they are independent from each other, the deterioration in performance due to the MIMO transmission has not been largely problematic. However, unlike the mobile communication system, in the case of the broadcasting system, the probability that correlation values will be generated between transmitting and receiving antennas increases. Therefore, when the existing spatial multiplexing scheme of MIMO transmission method is used under the channel situation of the broadcasting system described above, significant deterioration in performance may be generated. Therefore, a need exists for an improved MIMO transmission method for alleviating deterioration in performance at the time of MIMO transmission in a broadcasting system.